Snowball Earth
By Justin Gardner | Related entries in Environment, HistoryApparently, at one point in our planet’s history, global warming was a good thing, as it rescued Earth from being in a deep freeze forever.
An alternative look from CNET.
Humans apparently aren’t the first species to change the climate of the planet. Bacteria living 2.3 billion years ago could have plunged the planet into deep freeze, researchers at the California Institute of Technology claim in a new report.This entry was posted on Wednesday, August 3rd, 2005 and is filed under Environment, History. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.[...]
The Caltech team argues that 2.3 billion years ago, cyanobacteria, or blue-green algae, gained the ability to break down water, which in turn released a flood of oxygen into the atmosphere.
That oxygen reacted with the atmospheric methane, which insulated the Earth at the time, and broke it down. While the oxygen-methane reaction created the greenhouse gas carbon dioxide, the protective nature of the barrier cracked.
Temperatures plunged to minus 50 degrees Celsius, and ice at the equator grew to 1 mile thick. Although this process took several million years, substantial damage to the methane layer could have occurred in the first 100,000 years.
Life-forms only recovered after microorganisms, clinging then to thermal vents or living underground, evolved the ability to consume oxygen and turn it into carbon dioxide.
August 3rd, 2005 at 2:50 pm
Not to mention that the oxygen that the algae released was severely toxic to pretty much every living thing on the planet. (The few remnants from those times which survive do so in environments where oxygen can’t reach, like in the depths of the oceans.) The cold would have killed off a lot of life forms eventually. But the oxygen poisoned them a whole lot faster! Easy to overlook, since you now live in an ecology which requires what was once the worst toxin going.
Not to argue that global warming isn’t a valid issue. But toxic waste can be more urgent.
August 7th, 2006 at 12:49 am
Good job.